Liquid level gauge



Nov. 28, 1950 E. Y. GUTHMANN 2,531,774

\ LIQUID LEVEL GAUGE Filed March 13, 1947 5 Sheets-Sheet l Nov. 28, 1950 E. Y. GUTHMANN 2,531,774

LIQUID LEVEL GAUGE Filed March 13, 1947 I I5 Sheets-Sheet 2 a. Fig 5 H 6,

Nov. 28, 1950 E. Y. GUTHMANN LIQUID LEVEL GAUGE 3 Sheets-Sheet 3 Filed March 15. 1947 W w W K W Patented Nov. 28, 1950 ammo: LEVEDGAUGE Eugene or. 1 Gutlnnann, Plhil-adelphia fiar 'iipplication-March l 1947, Serial'N ;7341330 4= Glaims. 1

-'Ihis invention relates to liquid level indicators and i more "particularly to aliquid level gauge adapted *for use in locomotive tenders.-

A principal object of the invention is to prowide-an indicator of the stated class having a "simplifled and :generally improved structural "for-m and the compactness and --rug g'edness re -quired in a device properly adapted *for use in a locomotive tender.

Another'objectis to provide a "device of the stated"characterwwlrerein, by reason of inherent structural simplicity; lithe "absence of intricate -pa-rts; and a favorahly symmetrical arrangement of elements, friction is reduced to a ractical minimum and sensitivity correspondingly increased.

The invention resides further certain novel structural and mechanical details hereinafter described and'illustrated in the attached drawings wherein :Fig. 1 as a fragmentary elevational' sectional view showing one *end of a locomotive tender equipped with a tank gaugemade in accordance with the invention;

*Fig. 2 is an enlarged fragmentary sectional view showing the details "of the gauge device shown in Fig. 1;

Fig. 3 is a sectional view on'the' line 3--3,

Fig. 4 a "front =elevational view partly" in section of the Y indicator portion of the gaugeshown iii-Fig; *2;

Fig? 5 is an enlarged: sectional view-corresponding= to Fig. 2 and illustrating amodificatiomwithin thescope of the invention;

Fig. '6 is a sectional view on the line 6-6,

Fig. 5;

Fig. 7' is a front "elevational view of theindicator portion-of thedevice illustrateddn Fig. 5

with a portion of the coverlplate'of the indicator 'housi-ng cutaway to disclose the operation elements, and showing also a diagram dfthe asso- .eiated electrical system;

Fig. 9* is a view inperspective of a modified form (it indicator flevice;

'F'ig. lo-is an enlarged topwplan view of the devioe'shown in Fig; 9, apart of the casingbeing :broken away to disclose the "working elements Within;

jFig. 11 an enlarged front 'elevational "view 'oi thedevicesshowmin Figr .Fig'. mris a :sectionalwiew cache line 12-42, Fig. 9; i

Fig; 1131s a-rfragmentary:frontxelevationalview showinga modification :of the -device illustrated inxthaimm:diatel :preceding .:figures;

:chain M centrally through .Lthesstandard '=3, :the standard; may be provided "with guide wins .16

Fig; 114* is: a sectionoonithesline |-'|--l hi ls-11.3;

Fig. 15 iswa diagrammatic illustrationof :still anoth er form 'IOfI indicator: devica yand :Fig. l'filis amend view of "the assembly "shown in f'Fig. 1I5.

withrreferencento Figs. 1 to-4ainclusivexof -.the drawingsgthe reference "numeral I xindicates'zthe forward end of a" locomotive tender, the "side wall of the rtenderzbeingfbroken :away in order to expose a liquid level gauge indicated generally :by the -reference" numeral 2 1 which is mounted in the interiorhofi the? tank; Theugauge is'morewlearly illustrated in :E'ig.;2 wherein .it issshownasa comprising a tubular-standard 3 which isssecured' to thelbottom of" thertanlcbysmeans of ra-lowerterminal fitting 4, and which is similarlysecuredi-to the top wall :of "the tankthrough thetmediumriof atop terminal fittingj; The device also comprises a float i=6 "which; is arranged "to rise: and

fall 'withzthe liquid; level in .the .tank and which isuguide'din its upsand :down movementizby the comprises a central hollow cylindrical :portion '1- which -slidably' embraces" thezstandard 3 and which functionsras a weight-ion a purpose here"- inafter' set forth. The inner wall 8 rot @this member "1" is recessed so "that onl *a ssmallasurfacexarea :atthetop and bottom of thezmemrber'cactua'llycontacts the surface of thesstand- "ard r3,1:thusreducing frictional contactsbetween the element 1 :and-xthe standard .to a "minimum. 'flhezfloatunitxalso comprises athinc-walled casing Iewwhich extends-outwardly from :thexsid'es of the element J and which mislhermetically sealed'soas to function as'thefioat proper; 'It will be noted that this float structure is entirely symmetrical :about the vertical center line.

Mounted-at"the top and bottom respectively :of the -standardaiiv is a sprccket, H :and. 12 respeotively, "theseasprookets being suitably jourrna ledijinc-th emwall of the standard and projecting through suitable slotted? openings :13 insaid :wall. /A chain 14, attached ;at oneend tothe ttopwo-fstheifioat element lythrough themedium 'in :the presentinstanceofwa turn buckle I 5, extends :upwardly over the sprocket H, :rthence downwardlyin the interior of the standard 3 to'.-an'd under the sprocket l2, and egain 11p- "wardly' on the-outside of the standard andc'at the opposite "side thereof to a pointxof -connec- "tionuwithwthcbottom of the element I. Thus the :ltermi-naluends of' the chain M are connected respectivelywto the top and bottom ;of the float elemental at diametrically opposite 'sides ofwthe latter; If desired, and in order 'to :guide the and I! behind which the chain passes as clearly illustrated. If desirable each of these pins may be provided with a roller to reduce friction between the chain and the pins. It is to be noted that in the assembly the standard 3 functions both as a guide for the float and a housing for chain [4.

The hub ill of the sprocket H is attached to a threaded shaft l9, one end of this: shaft being journaled as indicated at 2 1, 2| in the walls of the standard 3 and the other end of the shaft projecting outwardly from the standard and being threaded for reception of a follower nut 22. Pivotally secured at 2G to the upper end of the nut 22 is a pin 23 which passes freely through an aperture 24 i the enlarged portion 25 of a shaft 26, this shaft being journaled in bearings 21,21 in the upper bracket fitting of the standard 3. One end of the shaft 26 is connected through a suitable coupling 28 with a stub shaft 29, this latter being mounted for rotation in a sealed fitting 3| in the end wall 32 of the tender I. The

outer end of the shaft section is embraced by a casing 33 secured against the. outer face of the wall 32, this casing forming a housing for a pointer element 34 secured to the outer end of the shaft 29. The pointer 34, as illustrated in Fig. 4, cooperates with a dial 35 which, as more fully described hereinafter, indicates theposition of the float 5 in the tank and which is graduated so as to afford a resonably accurate indication of the level of the water upon which the float is supported. The outer wall of the housing 33 is provided with an opening 36 through which the body portion of the pointer 34 is visible, and this body portion, which is enlarged as shown in Fig. 4, is provided with three segments 3?, 38 and '39 which may be colored respectively red, yellow and green. This device provides a. visual colored signal to indicate the general range of the liquid level in the tender tank.

The operation of the device as described above isas follows: When the tank I is filled with water the float 6 will ride to the top of the standard I 3 and in the process will rotate the sprocket H clockwise as viewed in Fig. 2 with the result that the shafts 26 and 29 will be rotated in clockwise direction as viewed in Fig. 4 thereby causing the pointer 34 to move downwardly toward the bot- -tom of the scale 35. This rotary movement of thfe shafts is efiected by translational movement of the nut 22 on the screw 59 and the resulting angular movement of the pin 23 and of the shaft 26. The ability of the pin 23 to move longitudinallyin the collar 25 of the shaft 26 compensates for the fact that the movement of the lower end of this pin, which is pivotally attached to the nut 22, is in a rectilinear path, the distances of various points of which with respect to the axis of the shaft 26 will vary.

" As" the water level gradually falls in the tank,

. the float ii will move downwardly with the result that the pointer 34 is gradually moved upwardly on the dial 35 toward the zero position into which it moves as the float approaches the bottom of the tank. When the tank is full the green of the segment 39 of the pointer appears in the opening 35. This color changes to yellow as the tank approaches the half-empty condition, and beyond this point will register red to indicate that the tank is nearing the empty condition.

' It is to 'be noted that the weight of the element 7 and the buoyancy of the element 9 of the float s'tructure'are'sufficient to overcome all frictional resi'stance in the moving parts of" the device and the tank.

insure that the float shall move with the water level. It will be noted also that the sprocket ll constitutes a medium for direct coordination of the concealed float 6 and the visible indicator 3435, and that there is a constant relation between the position. of the nut 22 on the sprocket actuated screw I9 and the elevation of the float 6 in the tank} The embodiment of the invention illustrated in Figs. 5 to 8 inclusive employs the same basic principle of operation as that described above. In this case, h'owever, the sprockets 4| and 42 are journaled in the top and bottom terminal fittings 43 and 44 of the standard assembly and are offset to opposite sides of the center line of the tubular standard member 45. With this arrangement the chain 46 may pass around the sprockets into a straight pass corresponding to the longitudinal center line of the said tubular standard. This avoids the necessity for the pins [6 and ll of the previously described embodiment or their equivalent and still further reduces friction loss in the device. Friction is still further reduced by provision in the float structure of rollersy50, at both top and bottom, which engage the standard 45 and preclude sliding friction between the standard and the said structure.

In. this case also it will be noted that the hub llof the sprocket 4! is internally threaded for reception of a threaded pin 48 which is slidably supported in a suitable guide 49 in the bracket fitting 43. This threaded pin thereby functions as a support for the sprocket 4| and also as a means for rotating the indicator shaft 5|. For this latter purpose one end of the pin 48 has a pivotal connection with a pin 52 which passes freely through a diametrically disposed aperture within the large end portion 53 of the shaft 5|. As the pin 48 is shifted longitudinally in the guide passage 49 as a result of rotation of the sprocket 4! and the threaded connection between the sprocket and the pin, the angularity of the pin 52 will be changed in obvious manner with the result that the indicator shaft-5| will be rotated.

The outer end of the shaft 5| carries a pointer 54, see Fig. 7, which coacts with a segmental dial 55 to indicate the position of the water level in In its movement from one extreme position to the other the pointer 54 successively engages three electrical contacts 56, 51 and 58,

see Fig. '7, thereby completing electrical circuits through three differently colored signal lamps,

59, GI and 62 respectively, whereby when the tank is nearing empty the lamp 59 will be energized as indicated in Fig. 7 to show a red light. When the tank is approximately half full the yellow light 6| will be energized to the exclusion of the others, and when the tank is full the green light 62 will be energized.

In general the operation of this embodiment of the invention is essentially the same as that of the embodiment previously described. Itwill be noted, however, that in this case means is provided for stopping the float at both ends of the travel thereof short of the sprockets. The lower stop is formed by the shoulder 63 at the top of the fitting 44, and a corresponding shoulder 64 at the lower end of the fitting 43 forms the upper trated in Figs. 9 to 12 inclusive is mounted on the top wall of the tender tank 55 instead of on the side as in the previously described embodiments. In this case the tubular standard 66, which corresponds to the standards 3 and 05 of the previously described embodiments, is extended upwardly through the top wall 61 of the tank and has suitably secured to the upper end thereof a bracket or frame structure 68 which forms a support for the working elements of the indicator including the upper sprocket 69 over which the float chain H is trained. In this case the sprocket 69 is supported on a threaded shaft 12 with which the sprocket is in threaded engagement. The shaft 12 is slidably supported in suitable guides in the frame 68, whereas the sprocket is confined in the frame against axial movement as well shown in Fig. 10. When the sprocket is turned the shaft 12, by reason of the aforesaid threaded engagement, is traversed longitudinally in one direction or the other, depending upon the direction of sprocket rotation.

Secured to one end of the shaft 72 is a pointer element 13 which as the shaft is traversed longitudinally is caused to move over a dial 14 containing marks related to the depth of the liquid in the tank.

The frame 68 and the several operating elements mentioned above are housed within a removable casing which in the present instance is pivotally secured to the frame as indicated at 15 so that it may be elevated to afford access to said operating parts, the opposite end of the easing being provided with a spring clip 16 which normally holds the casing in closed position as shown in Fig. 11. In the present instance the casing is provided with a transparent window 71 through which the pointer 13 and dial 14 are visible from the front of the tender.

The operation of this embodiment will be clear from the foregoing description and it will be noted that the straight line motion of the pointer 13 afforded by the use of a longitudinally traversable threaded shaft is calculated to afford an extremely accurate indication of the changing level of liquid in the tank.

The modification illustrated in- Figs. 13 and 14 corresponds essentially to that illustrated in Figs. 9 to 12 inclusive, but differs from the latter in that the threaded shaft 18 which actuates the indicator pointer 19 is fixed against axial movement and is merely rotated by the actuating sprocket 8|. The pointer 19 is mounted upon a follower nut 82 which has threaded engagement with the shaft 18 and which is slidably mounted on the frame 83, means being provided as indicated in Fig. 14 for preventing rotation of the follower nut 82 about the axis of the shaft 18. In this case actuation of the sprocket 8| by movement of the float in the tank is translated into longitudinal movement along th shaft 18 of the pointer 19. The usual dial 84 is provided for cooperation with the pointer 19 and the elements are arranged so that the position of the pointer 19 on the dial 84 is a true index of the level of the Water in the tender tank.

In Figs. 15 and 16 a. corresponding device is disclosed employing a rack and pinion for actuation of the dial pointer 85. The sprocket 86 on which the float chain 81 operates is carried by a shaft 88 at one end of which is mounted a pinion 89. This pinion meshes with a toothed rack 9| which is mounted in the supporting structure for longitudinal sliding movement. As illustrated the pointer 85 is carried by the rack.

Rotation of the sprocket 86 in this instance results in a corresponding longitudinal movement of the rack 9i and movement of the pointer across the dial of the indicator. This type of indicator actuating mechanism has an advantage residing in the fact that the traverse movement of the pointer may be made relatively great in proportion to the angular movement of the actuating sprocket by merely increasing the diam eter of the rack pinion whereby a relatively wide spacing of the dial indications is practical. 0bviously the rack 9| may be other than straight if desired and may in fact take the form of a gear, either external or internal. Obviously also, the dial scale may be applied to the rack for cooperation with a fixed pointer without departing from the invention.

I claim:

1. In a liquid level indicator, a float adapted to rise and fall with the level of said liquid, a standard constituting a guide for said float, a sprocket at top and bottom respectively of said standard, a chain having its ends secured to the float re spectively at opposite sides of said standard, said chain passing around each of said sprockets and extending from one of said sprockets to the other substantially in alignment with the vertical center line of said float, and means associated. with one of said sprockets for indicating the position of the float between said sprockets.

2. In a liquid level indicator, a float adapted to rise and fall with the level of said liquid, a standard constituting a guide for said float, a sprocket at top and bottom respectively of said standard, a chain having its ends secured to the float respectively at opposite sides of said standard, said chain passing around each of said sprockets and extending from one of said sprockets to the other and said sprockets being relatively offset to opposite sides of the vertical center line of said float so that the portion of the chain passing from one to the other of the sprockets will follow a straight path along said center line, and means associated with one of said sprockets for indicating the position of the float between said sprockets.

3. A liquid level indicator according to claim 1 wherein the float embraces the standard which is made hollow to afford a passageway for the chain in passing from one to the other of said sprockets.

4. A liquid level indicator according to claim 2 wherein the float embraces the standard which is made hollow to afford a passage for the straight line run of the chain extending from the one sprocket to the other.

EUGENE Y. GUTHMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 763,716 Bray June 28, 1904 1,270,655 Page June 25, 1918 1,378,327 Cox May 17, 1921 1,504,025 Corset Aug. 51, 1924 1,918,672 Szabo July 18, 1933 FOREIGN PATENTS Number Country Date 303,474 Italy Dec. 3, 1932 357,799 Italy Mar. 28, 1938 

